Pressurized fluid delivery systems are used in a wide variety of industrial applications. By way of non-limiting example, sprinkler systems are often installed in industrial buildings for fire protection purposes. Such sprinkler systems are often equipped with flow or pressure sensors positioned at various points in the distributed flow system, which sensors may automatically detect and generally manage the flow of fluid through the system, and may initiate alarms in the event that a particular alarm event is triggered. For example, in the event of a fire at an industrial facility, the sprinkler system may be equipped with mechanisms that automatically detect the fire and automatically activate the sprinkler system. Flow or pressure sensors in the system may detect the increased fluid flow, and may automatically signal an alarm to, for example, call the fire department or other personnel to combat the fire. Such flow or pressure sensors typically comprise a switch having a water flow detector, which is an electro-mechanical device designed to send an alarm to a fire alarm panel and/or a fire department when a continuous flow of water occurs through the fire sprinkler system's piping as a result of an activated fire sprinkler head. A portion of an exemplary industrial sprinkler system is shown in FIG. 1, including a fluid riser 10 and a flow or pressure switch 20 positioned on the riser.
FIG. 2 is a close-up view of an exemplary flow or pressure switch 20 of traditional configuration, and includes a cover 22, a base 24, and a fluid line tap 26. The cover 22 may be attached to base 24 by screws or similar fasteners.
Such industrial fluid delivery systems require periodic maintenance. Unfortunately, there are service personnel that, from time to time when servicing such systems, interfere with the operation of the flow or pressure switches so as to ensure that an alarm condition is not triggered while they are performing their intended service. More particularly, as the flow or pressure switch 20 is typically connected to a supervised fire alarm or monitoring panel that automatically calls the fire department when activated, often service personnel attempt to disable the flow or pressure switches 20 so that they may perform the intended service without interference. Such service personnel may not have access to the fire alarm or monitoring panel, and may lack the knowledge or authority that would be required to temporarily disable the alarm (account numbers, passwords, etc.), but are nonetheless tasked with performing the needed service as quickly as possible. It has become a not uncommon practice for certain service personnel to break off portions of the flow or pressure switch 20 assembly so as to be able to remove cover 22 from base 24, allowing access to the switch activator which they may then manually manipulate and block from moving. This allows the service personnel to drain and refill the sprinkler system without triggering an alarm. However, such practice creates multiple problems. First, damage done to remove cover 22 from base 24 results in cover 22 no longer fitting on base 24, or at a minimum not properly fitting on base 24, thus exposing switch 20 to weather, moisture, and the like. Second, in order to repair such a damaged flow or pressure switch 20, the property owner or other responsible party is faced with an expense of potentially $500 per switch. Third, inoperative flow and pressure switches will fail to automatically dispatch the fire department in a fire emergency and could create a life threatening situation.
Thus, there is a need in the art for a mechanism that would prevent unauthorized access to flow or pressure switches on pressurized fluid delivery systems, but that is easy to install and remove, and of sufficiently simplistic construction to be manufactured at low cost so that it may be affordably deployed on systems having large numbers of such flow or pressure switches.